Houston Mayor Sylvester Turner argued on Sunday that an evacuation of Harris County, which is seeing "unprecedented" flooding in the aftermath of Hurricane Harvey, would have led to a far worse calamity for area residents.

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"If you think the situation right now is bad, you give an order to evacuate, you are creating a nightmare. Especially when it's not planned," Turner said during an update Sunday on the city's response to Harvey.

"If you do it or attempt to do it and it's not coordinated, not done right, you are literally putting people in harm's way, and you're creating a far worse situation," he said.

Turner, who was elected in 2015, stood by his decision not to issue an evacuation order for Houston because, while the city anticipated a lot of rain, the city was not in Harvey's direct path.

He said that because of the flooding, every neighborhood would have to be evacuated, which is "dangerous."

"You cannot put, in the city of Houston, 2.3 million people on the road. That is dangerous," Turner said. "When you combine Houston and Harris County, you literally cannot put 6.5 million people on the road."

He said the best place for people is to be in their homes.

Hurricane Harvey, which weakened to a tropical storm by Saturday afternoon, has led to record levels of rainfall in the Houston area and has so far left three people dead.